Construction of a high-density genetic linkage map and QTL analysis of morphological traits in an F1 Malusdomestica × Malus baccata hybrid

Huacheng Cai; Qian Wang; Jingdong Gao; Chunyan Li; Xuemei Du; Baopeng Ding; Tingzhen Yang

doi:10.1007/s12298-021-01069-0

Construction of a high-density genetic linkage map and QTL analysis of morphological traits in an F1 Malusdomestica × Malus baccata hybrid

Physiol Mol Biol Plants. 2021 Sep;27(9):1997-2007. doi: 10.1007/s12298-021-01069-0. Epub 2021 Sep 23.

Authors

Huacheng Cai^{1

2}, Qian Wang^{1

2}, Jingdong Gao^{1

2}, Chunyan Li^{1

2}, Xuemei Du^{1

2}, Baopeng Ding^{1

3

4}, Tingzhen Yang^{1

2}

Affiliations

¹ Pomology Institute, Shanxi Agricultural University, Taigu, 030801 Shanxi China.
² Shanxi Key Laboratory of Germplasm Improvement and Utilization in Pomology, Taiyuan, 030031 Shanxi China.
³ College of Horticulture, Shanxi Agricultural University, Taigu, 030801 Shanxi China.
⁴ College of Forestry, Shanxi Agricultural University, Taigu, 030801 Shanxi China.

Abstract

Apple is considered the most commonly grown fruit crop in temperate regions that brings great economic profits to fruit growers. Dwarfing rootstocks have been extensively used in apple breeding as well as commercial orchards, but the molecular and genetic basis of scion dwarfing and other morphological traits induced by them is still unclear. At present, we report a genetic map of Malusdomestica × Malus baccata with high density. The F₁ population was sequenced by a specific length amplified fragment (SLAF). In the genetic map, 5064 SLAF markers spanning 17 linkage groups (LG) were included. Dwarf-related and other phenotypic traits of the scion were evaluated over a 3-year growth period. Based on quantitative trait loci (QTL) evaluation of plant height and trunk diameter, two QTL clusters were found on LG 11, which exhibited remarkable influences on dwarfing of the scion. In this analysis, QTL DW2, which was previously reported as a locus that controls dwarfing, was confirmed. Moreover, three novel QTLs for total flower number and branching flower number were detected on LG2 and LG4, exhibited the phenotypic variation that has been explained by QTL ranging from 8.80% to 34.80%. The findings of the present study are helpful to find scion dwarfing and other phenotypes induced by rootstock in the apple.

Supplementary information: The online version contains supplementary material available at 10.1007/s12298-021-01069-0.

Keywords: Apple; Dwarfing; Genetic linkage map; QTL; SLAF-seq.